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SYNTAX      DIRECT   [<LABEL>] ZALS <dma>
            INDIRECT [<LABEL>] ZALS {ind}[,<next ARP>]

OPERANDS    0 . dma . 127; 0 . next ARP . 7.

EXECUTION   (PC) + 1 . PC
            0 . ACC(31-16)
            (dma) . ACC(15-0)
            Not affected by SXM.

DESCRIPTION The contents of the addressed data memory location are loaded
            into the 16 low-order bits of the accumulator. The upper half
            of the accumulator is zeroed. The data is treated as a 16-bit
            unsigned number rather than a two's complement number.
            Therefore, there is no sign-extension with this instruction,
            regardless of the state of SXM. ZALS behaves the same as a LAC
            instruction with no shift and SXM = 0.

            ZALS is useful for 32-bit arithmetic operations.

WORDS       1

ENCODING    15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0
            +-----------------------------------------------+
            |0  1  0  0  0  0  0  1| 0| data memory address | DIRECT
            +-----------------------------------------------+

            15 14 13 12 11 10  9  8  7  6  5  4  3  2  1  0
            +-----------------------------------------------+
            |0  1  0  0  0  0  0  1| 1| see indirect fields | INDIRECT
            +-----------------------------------------------+

CYCLES

            +------------------------------------------------+
            |    Cycle Timings for a Single Instruction      |
            |------------------------------------------------|
            | PI/DI | PI/DE | PE/DI | PE/DE  | PR/DI | PR/DE |
            |-------+-------+-------+--------+-------+-------|
      '20   |   1   |  2+d  |  1+p  | 2+d+p  |   -   |   -   |
            |-------+-------+-------+--------+-------+-------|
     'C25   |   1   |  2+d  |  1+p  | 2+d+p  |   1   |  2+d  |
            |------------------------------------------------|
            |    Cycle Timings for a Repeat Instruction      |
            |------------------------------------------------|
      '20   |   n   | 2n+nd |  n+p  | 2n+nd+p|   -   |   -   |
            |-------+-------+-------+--------+-------+-------|
     'C25   |   n   | 1+n+nd|  n+p  |1+n+nd+p|   n   |1+n+nd |
            +------------------------------------------------+



EXAMPLE     ZALS  DAT1        (DP = 6)
            or
            ZALS  *           If current auxiliary register contains 769.

                        BEFORE            AFTER

               dm769     >F7FF     dm769  >F7FF
               ACC X >7FF00033      ACC X >F7FF
                   C                    C


            .